The article of which you speak (MOHAMAD ALI RIDA and DAFNA D. GLADMAN
The Journal of Rheumatology August 2020, 47 (😎 1297; DOI: https://doi.org/10.3899/jrheum.191292) references only a single case. And while this may appear on the surface as promising, human trials have been limited, and mostly conducted to test the safety of black seed oil. I'm all for people trying whatever may work, but a few things need be considered. In the US, there are essentially no regulatory restrictions on anything marketed as a "supplement". So there are virtually no limits to the claims that may be put on these things, so long as they don't claim that their product can treat or prevent disease. Nor are there any real restrictions on what a manufacturer has to reveal goes into a supplement. And when companies do violate what few laws govern the supplement industry, the government is often very slow to reac. Even if there were numerous long term human trials showing the efficacy of this Black Oil on PsA (there aren't), there is no regulatory body that would ensure the purity, or even the amount, of it that goes into a supplement. You could be paying hundreds of dollars for something that has barely a drop of black oil, and might contain high levels of toxic compounds to boot. So if you do opt for this supplement, do your research on what has been found to be a safe amount of it to take, daily and in total, and look into the company producing it.